1. Field of the Invention
The present invention is in the field of connectors for electrically interconnecting electrical conductors of electrical cables, and in the field of method of making such connectors. More particularly, the present invention is in the field of connectors for multi-conductor electrical cables, in which the connector provides for individual connection of each conductor of the multi-conductor electrical cable to a corresponding electrical conductor of another multi-conductor electrical cable, or to other structure.
2. Related Technology
Current technology includes a wide variety of multi-conductor electrical cables, and a similarly wide variety of connectors for such cables. These connectors generally provide for individual connection of the electrical conductors of a cable either to the corresponding conductors of another cable or to other electrical structure. For example, in the home, the common two-conductor or three-conductor electrical extension cord for house-current is well-known. This extension cord includes a male connector plug at one end and a female connector receptacle at the other end.
Another common example of a multi-conductor electrical cable connector is the modular telephone connector presently in wide use. This connector provides for electrically connecting up to five conductors of a telephone cable either to five corresponding conductors of another length of telephone cable, or to corresponding conductors of another structure, such as a telephone. In the case of both the house-current extension cord and the modular telephone connector, the actual electrical interconnection between cables or other structures is effected by mutual contact of pre-formed or stamped metallic contacts carried by a pair of connectors. Frequently, these metallic contacts are formed of a springy and shape-retaining material, such as phosphor-bronze. When the connectors of a pair are engaged with one another, the contacts distort slightly into electrical contact as the male and female components of the connector pair, such as a plug and receptacle, for example, are engaged with one another.
In the process of manufacturing many connectors for multi-conductor electrical cables, the pre-formed contacts are attached by soldering or crimping to individual end portions of each conductor from which the electrical insulation has first been stripped. Subsequently, these contacts are placed into receiving portions of a mold cavity which also has provision for sealingly closing about the adjacent length of cable. This mold cavity defines a void space which is configured to the selected shape of the finished connector. The mold cavity void space may be filled with a thermoplastic insulative material, such as polyvinylchloride, for example, or with a thermoset insulative material, such as natural or synthetic rubber. Injection molding or transfer molding, for example, may be used to fill the mold cavity void space with insulative material. After the insulative material cools or cures, the cable and connector with electrical contacts completely enclosed (in the case of a female connector) or partially embedded in insulative material and outwardly projecting therefrom (in the case of a male connector), is removed from the mold cavity.
As can be appreciated from the above, the conventional cable connectors require the fabrication of plural component parts, and the performance of plural manufacturing steps in order to complete the connector. All of these component parts and plural manufacturing steps add to the overall cost of a conventional cable connector. Also, the multiplicity of parts and manufacturing steps for a conventional cable connector increases the opportunity for variability in the manufacturing process, and for quality control problems and high scrap rates.
A conventional multi-conductor electrical cable and connector is known in accord with U.S. Pat. No. 4,703,989, issued 3 Nov. 1987, to J. R. Price, et al. The electrical connector and cable of the '989 patent are employed to connect a disposable blood pressure monitoring assembly to a durable, or reusable, cable and connector. This latter durable cable and connector are connected to a blood pressure monitoring apparatus. The connector and cable of the disposable blood pressure sensor assembly employs plural individual electrically conductive blade members of the so called, "insulation-displacement" type to penetrate the insulation of the cable into electrical contact with the corresponding electrical conductors. These insulation-displacement blades then provide for electrical connection of the respective conductors of the cable to corresponding contacts of the connector carried on the durable cable extending to the monitor.
With a cable connector according to the '989 patent, all of the deficiencies of conventional cable connectors apply. Further, because the cable, its connector, and a molded housing for the blood pressure sensing unit may be manufactured together in a semi-continuous process, defects in the connectors which render them unusable also require the connected length of cable and molded sensor housing also to be scrapped.